I like to run a heavy duty spring and H2 buffer in all my carbine-length guns, suppressed or not. It won't make any appreciable difference in wear. I've tried the Gas Buster and it's ok, but it doesn't really help much. The worst part of gassy-face is all the ammonia in the smoke makes your eyes and nose burn like hell with a high volume of fire.

Another option I like is Spike's T2 buffer. About the same weight as an H2, but uses powdered tungsten instead of weights. Less banging around and seems to shoot a little softer.